Justin Bieber Strikes Back: "I'm Young and I Make Mistakes"

Justin Bieberon the verge of a breakdown? You better NOT believe it. After a series of bizarre incidents led to speculation that Bieber is heading for a meltdown, the 19-year-old pop star defends himself in an exclusive chat with Us Weekly's Entertainment Director Ian Drew.

"The biggest misconception about me is that I'm a bad person," confides Bieber. "I get upset about that. I have a big heart. I want to be a good role model, but some people want me to fail."

Not that he hasn't publicly stumbled lately. On Feb. 28, Bieber was photographed heading into his London hotel shirtless. "I still had part of my tour wardrobe on and was rushing into my hotel," explains the "Boyfriend" singer, who was photographed shirtless again in an airport in Poland on March 25.

But the "As Long as You Love Me," singer assures, "I passed out from the flu. The worst thing to me is disappointing my fans -- we only had five songs left -- so they gave me oxygen, and I decided to finish the show and then go to the hospital. The show must go on."

As for the gas mask, he says it's "a joke with my friends."

"I wanted to hide my face from all the cameras," he explains. "They got it as a joke. My friends and I like messing around.

That said, he admits he's far from perfect. "I'm young and I make mistakes. That's part of growing up," he says. "I mess up sometimes. It's part of growing up."

For now, the unattached heartthrob is tuning out his detractors. (He wraps up his nearly yearlong world tour in August.) "I know who I am and I'm not gonna let negativity towards me bring me down. I'm a positive person and I plan on staying that way," Bieber says. "This business can break you down, but I have a strong team around me, and my family and all the fans. The love overcomes the negativity. I'm not perfect but I'm growing and trying to be better everyday. That's part of life."

Still, Bieber adds, "I'm young and I want to have fun. I don't think there is anything wrong with that."